Black soybean has high medicinal purposes and health care value，it also has high agricultural increment potential，the distribution of black soybean in China is broad，it had been widely produced in northeast China，Shandong，Shaanxi，Henan and other provinces.To provide theory basis for high yield black soybean cultivation，black soybean cultivar Liaohei 1 was used as material，the effect of topdressing nitrogen in flowering period and no bottom fertilizer was studied，four nitrogen fertilizer treatment of 0 kgha-1(N0)，45 kgha-1(N1)，90 kgha-1(N2）and 90 kgha-1in addition of 22.5 kgha-1by spraying on leaves surface（N3）were used.The effect of 4 kinds of nitrogen level on yield and the rules of accumulation and distribution in nitrogen，phosphorus and potassium were discussed.The results indicated that nitrogen fertilizer not only enhanced the dry matter accumulation and yield but also facilitated the partition of nitrogen，phosphorus and potassium to the seeds.The yield was highest under the treatment of N1，while the most nitrogen was accumulated under the treatment of N2.Compared with the treatment of N0，all the treatments were helpful to the partition of nitrogen to the seeds，while the partition was highest under the treatment of N1.The influence of different nitrogen fertilizer levels on absorbtion and distrubution of phosphorus was the same to the nitrogen.Nitrogen fertilizer was helpful to the partition of potassium to the seeds，and there were no significant difference in each treatment.In the production it was suggested that the yield of black soybean could be obviously increased under the nitrogen of 45 kgha-1.

[12]蒋工颖，董钻.大豆养分吸收动态及施肥效果的研究[J].作物学报，1989，15(2)：167-173.(Jiang G Y，Dong Z.Studies on the trends of nutrient uptake and effect of fertilizer application on soybean[J].Acta Agronomica Sinica，1989，15(2)：167-173.)

[13]史占忠.大豆植株全氮磷钾含量变化分析[J].大豆科学，1989，4(3)：369-373.(Shi Z Z.The variation of content of total nitrogen，phosphorous and potasstium in soybean plants[J].Soybean Science，1989，4(3)：369-373.)

[14]毕远林.大豆干物质积累与氮、磷、钾吸收与分配的研究[J].大豆科学，1999，18(4)：331-335.(Bi Y L.Study on accumulation of dry matter and absorption and distribution of nitrogen，phosphorous and potasstium in soybean[J].Soybean Science，1999，18(4)：331-335.)

[15]赵玉臣，严红.大豆吸收氮磷钾的营养规律及其产量、品质效应的研究[J].土壤通报，1989，20(1)：34-36.(Zhao Y C，Yan H.Studies on nutrition law of the absorption of nitrogen，phosphorous and potasstium and the response of the yield and quality in soybean.[J].Chinese Journal of Soil Science，1989，20(1)：34-36.)

[16]吴魁斌，戴建军.不同施氮水平对大豆产量及氮肥利用率的影响[J].东北农业大学学报，1999，30(4)：339-341.(Wu K B，Dai J J.Study on the influnce of 15N-urearate on the yield and fertilizer utilization efficency of soybean[J].Journal of Northeast Agricultural University，1999，30(4)：339-341.)